{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:45:09Z","timestamp":1760240709145,"version":"build-2065373602"},"reference-count":51,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2019,8,30]],"date-time":"2019-08-30T00:00:00Z","timestamp":1567123200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Taiwan Ministry of Health and Welfare Clinical Trial and Research Center of Excellence","award":["MOHW108-TDU-B-212-133004"],"award-info":[{"award-number":["MOHW108-TDU-B-212-133004"]}]},{"name":"Academia Sinica Taiwan Biobank Stroke Biosignature Project","award":["BM104010092"],"award-info":[{"award-number":["BM104010092"]}]},{"name":"NRPB Stroke Clinical Trial Consortium","award":["MOST 108-2321-B-039-003-"],"award-info":[{"award-number":["MOST 108-2321-B-039-003-"]}]},{"DOI":"10.13039\/100010792","name":"Tungs' Taichung Metroharbor Hospital","doi-asserted-by":"publisher","award":["TTMHH-108R0029"],"award-info":[{"award-number":["TTMHH-108R0029"]}],"id":[{"id":"10.13039\/100010792","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Tseng-Lien Lin Foundation","award":["not applicable."],"award-info":[{"award-number":["not applicable."]}]},{"name":"Taoyuan Armed Forces General Hospital, Taiwan","award":["AFTYGH-10718"],"award-info":[{"award-number":["AFTYGH-10718"]}]},{"name":"Katsuzo and Kiyo Aoshima Memorial Funds","award":["not applicable."],"award-info":[{"award-number":["not applicable."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJERPH"],"abstract":"<jats:p>Background: Studies have linked some bacterial infections with an increased likelihood for development of dementia. However, there is a paucity of data on the relationship between dementia and leptospirosis. In view of this, we conducted a retrospective cohort study to determine whether leptospirosis is a risk factor for dementia. Methods: Data were collected from the Taiwan National Health Insurance Research Databases (2000\u20132010) to investigate the incidence of and risk factors for dementia in patients with leptospirosis. Patients with leptospirosis who did not have a history of dementia were enrolled in the study. For each leptospirosis patient, four controls were randomly selected after frequency matching of age, sex, and index date. Cox proportional hazard regression models were used for the analyses of dementia risk. Results: A greater risk of dementia was observed in the leptospirosis cohort than in the non-leptospirosis cohort both in patients without any comorbidity (adjusted HR (aHR) = 1.23, 95% CI = 1.06\u20131.43) and with a comorbidity (aHR = 2.06, 95% CI = 1.7\u20132.5). Compared with the non-leptospirosis cohort without these comorbidities, the leptospirosis cohort with \u22652 comorbidities exhibited a significantly increased risk of dementia (aHR = 6.11, 95% CI = 3.15\u201311.9), followed by those with any one comorbidity (adjusted HR = 3.62, 95% CI = 1.76\u20137.46). Conclusions: Patients with leptospirosis were at a 1.89-fold greater risk of subsequent dementia, but potential genetic susceptibility bias in the study group is a major confound.<\/jats:p>","DOI":"10.3390\/ijerph16173168","type":"journal-article","created":{"date-parts":[[2019,8,30]],"date-time":"2019-08-30T10:31:17Z","timestamp":1567161077000},"page":"3168","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Risk of Dementia in Patients with Leptospirosis: A Nationwide Cohort Analysis"],"prefix":"10.3390","volume":"16","author":[{"given":"Chun-Hsiang","family":"Chiu","sequence":"first","affiliation":[{"name":"Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center Taipei, Taipei 11490, Taiwan"},{"name":"Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei 11221, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Po-Chung","family":"Chen","sequence":"additional","affiliation":[{"name":"Division of Family Medicine, Department of Community Medicine, Taoyuan Armed Forces General Hospital, Taoyuan 32549, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying-Chuan","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Family Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei 11490, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng-Li","family":"Lin","sequence":"additional","affiliation":[{"name":"Management Office for Health Data, China Medical University Hospital, Taichung 40402, Taiwan"},{"name":"College of Medicine, China Medical University, Taichung 40402, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Feng-You","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Taichung Tzu Chi Hospital, Taichung 42743, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chia-Chang","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Urology, School of Medicine, College of Medicine, Taipei Medical University, Taipei 11042, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4453-0068","authenticated-orcid":false,"given":"Kuang-Hsi","family":"Chang","sequence":"additional","affiliation":[{"name":"Department of Medical Research, Tungs\u2019 Taichung Metroharbor Hospital, Taichung 43503, Taiwan"},{"name":"Institute of Biomedical Sciences, China Medical University, Taichung 40402, Taiwan"},{"name":"General Education Center, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli 35664, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,8,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"296","DOI":"10.1128\/CMR.14.2.296-326.2001","article-title":"Leptospirosis","volume":"14","author":"Levett","year":"2001","journal-title":"Clin. 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